New images of the interstellar medium provided by Herschel and Planck bring spectacular evidence of the intricate and filamentary structure of the interstellar medium, betraying its turbulent nature. Although turbulence is a subject of interest in astronomy, little is know about the origin of turbulence in the interstellar medium. We suggest that part of the turbulence in the Orion molecular cloud be due to the decay of the Kelvin-Helmholtz instability.